Abrading apparatus



April 5, 193s. K. H. Bmw-:N` y 2,113,106

ABRADING APPARATUS Filed Sept. 22, 1957 Patented Apr. 5, 1938 UNITED STATES ABRADING APPARATUS Kenneth H. Bowen, Auburn,-N. Y., assignor to Columbian Rope Company, Auburn, N. Y., a corporation of New York Application September 22, 1937, Serial No. 165,177

6 Claims.

This invention relates to improvements in abrading apparatus and, particularly, to that type of apparatus wherein a sheet of abrasive materil is mounted upon a rotatable support commonly known as a pad.

These so-called pads are usually composed essentially of a brous material and a binder compressed in disc-like form to a density and thickness which will permit the pad to flex laterally in order that it, together with the sheet of abrasive material carried thereby, may accommodate itself to the surface of the object being operated upon. Due to this flexing of the pad and, of course, the sheet of abrasive material,

there is a tendency toward frictionalengagement between the contacting surfaces of the pad and said sheet of abrasive material, thus causing undue wear on the pad, and the primary object of the present invention is to provide means for minimizing, or eliminating, this frictional engagement, thus increasing the life of the pad.

A further object of the invention is to provide means for lubricating the contacting surfaces of the sheet of abrasive material and pad which will decrease the coeflicient of friction and hence decrease the abrasive wear on the pad but which will not detrimentally affect the binder and fibre structure of the pad.

A still further object of the invention is to provide means for lubricating contacting surfaces of the pad and sheet of abrasive material, whereby the supply of lubricant to these surfaces will be constantly replenished.

With these and other objects in view, the invention consists in certain details of construction and combinations and arrangements of parts, all as will hereinafter be more fully described, and the novel features thereof particularly pointed out in the appended claims.

In the accompanying drawing, illustrating a preferred embodiment of the invention- Figure 1 is a perspective view of the pad, with the sheet of abrasive material partly turned back;

Fig. 2 is a transverse sectional View of the pad and sheet of abrasive material;

' Fig. 3 is a perspective view of the 'rear of the sheet of abrasive material, with the lubricant applied thereto; and

Fig. 4 is an enlarged detail sectional View of the pad and sheet of abrasive material.

vAs previously indicated, the present type of abrading apparatus comprises a pad I0, generally of fibre construction and a binder, such as latex cement, against one surface of which a sheet or disc Il, carrying a granular substance l2, is removably attached. This detachability of the disc l l is for the purpose of permitting ready renewal of the abrasive, because, under normal operating conditions, the abrasive material on the disc is depleted, probably, within thirty (30) minutes. As is well understood, the pad, together with the disc of abrasive material is rotated at 'a comparatively high speed and pressed against the surfaces of the object being operated upon and, in order that the pad may accommodate itself to the contour of that surface, it is adapted to flex laterally while rotating. Due to this exing of the pad, there is a relative movement between the pad and disc carrying the abrasive and the frictional engagement between these surfaces inevitably Wears away, to a noticeable extent, the pad, so that the thickness thereof and, therefore, its rigidity, is gradually diminished. In order to overcome this difliculty, the present invention contemplates the use of a lubricating substance between these contacting surfaces of the disc and pad but, in view of the fact that the pad is composed essentially of bres, it is necessary that a lubricant be used that will not affect the binder or destroy its bonding properties. For this reason, a wax is preferred. For instance, candelilla wax, cannabis wax, beeswax,

or parafln, may be used, or any of these waxes may be used in combination with mica or graphite. Any of these lubricants will materially reduce the coeflicient of friction without destroying or detrimentally affecting the binder material.

In the preferred embodiment of the invention, this lubricant, whatever its form, is preferably carried by the disc Il, because it may not only be impractical to impregnate the pad itself with the wax, but even if the lubricant were applied directly to the pad, it would, no doubt, be gradually dissipated and, under some circumstances, might prove detrimental to the fibre structure. Therefore, more protection is afforded by having the lubricant carried by the disc Il. In addition, by having the lubricant carried by the disc Il, there will be a more or less automatic constant replenishment of lubricant because, as previously pointed out, these discs of abrasive material have a life of approximately twenty (20) or thirty (30) minutes under normal operating conditions, so that by the more or less constant replacement of paper discs there is, at the same time, a constant replenishment of lubricant. As will be appreciated, with this film of lubricant interposed between the paper sheet and the contacting surface of the pad, the frictional contact between the contacting surfaces of these two elements will impose very little, if any, wear on the fibrous structure of the pad, thus materially increasing the life of the pad.

Latex cement has been indicated as the preferred binder, but other materials can be used, such as casein and hide glues and combinations of these materials or with other binders. None of them will be detrimentally affected by the lubricants specified.

What I claim is:

1. In an abrading apparatus comprising a laterally exible pad and a disc of abrasive material detachably secured against a side surface of said pad, a lubricating substance interposed between the contacting surfaces of said pad and disc to eliminate friction between said surfaces during exing of said pad and disc.

2. In an abrading apparatus comprising alaterally flexible pad composed essentially of vegetable bres and a disc of abrasive material detachably secured against a side surface of said pad, a lm of lubricant on the surface of said disc in contact with said pad whereby frictional engagement of the contacting surfaces of the sheet and pad under lateral flexing is minimized.

3. In an abrading apparatus comprising a laterally flexible pad composed essentially of vegetable bres and a binder, a disc of abrasive substance removably secured against one of the side surfaces of said pad, a body of lubricant on the face of said disc contacting the pad surface to minimize frictional engagement between the contacting surfaces of the pad and disc under lateral flexing of said elements, said lubricant being nondestructive of the binder ingredient of the pad.

4. In an abrading apparatus comprising a laterally flexible pad composed essentially of vegetable fibres and a disc of abrasive substance removably secured against one of the side surfaces of said pad, a body of lubricant on the face of said disc contacting the pad surface to minimize frictional engagement between the contacting surfaces of the pad and disc under lateral flexing of said elements, said lubricant being selected from a group consisting of candelilla wax; cannabis wax; mica; graphite; beeswax and paraffin.

5. A body of abrasive material comprising a backing member with granular abrasive substance on one surface thereof, and a film of lubricant on the opposite surface of said backing member.

6. A body of abrasive material comprising a backing disc with a granular abrasive substance on one surface thereof, and a film of lubricant on the opposite surface thereof, said lubricant being selected from a group consisting of candelilla wax; cannabis Wax; mica; graphite; beeswax and parafn.

KENNETH H. BOWEN. 

